1. Field of the Invention
The present invention relates to a vehicle bumper including a pedestrian collision detection apparatus.
2. Description of Related Art
In a collision detection apparatus for a vehicle that is disclosed in Japanese Patent Application Publication No. 2010-179668 (JP 2010-179668 A), a chamber member is disposed on a vehicle front side of a bumper reinforcement. In addition, an absorber member is disposed between the bumper reinforcement and a bumper cover. The absorber member includes an absorber main body that is disposed on a vehicle lower side of the chamber member and a spacer section that is disposed on the vehicle front side of the chamber member. Accordingly, a gap between the bumper cover and the chamber member is filled by the spacer section. Furthermore, an upper portion at a front end of the spacer section is projected to the vehicle front side (bumper cover side), thereby preventing deformation of the bumper cover.
For example, during a collision of the vehicle (bumper cover) with a pedestrian, the spacer section presses the chamber member, and pressure in a chamber space in the chamber member changes. Furthermore, a pressure sensor outputs a signal that corresponds to a pressure change in the chamber space to a pedestrian protection device ECU, and then the pedestrian protection device ECU determines whether or not a collision body with the bumper cover is a pedestrian. As the collision detection apparatus for a vehicle, those disclosed in Japanese Patent Application Publication No. 2010-132040 (JP 2010-132040 A) and Japanese Patent Application Publication No. 2011-143825 (JP 2011-143825 A) can be raised.
However, because the absorber member is formed of a foaming resin material, a temperature change of the absorber member is relatively large. Thus, a structure of the vehicle collision detection apparatus in which the gap between the bumper cover and the chamber member is filled by the spacer section of the absorber member may be affected by the temperature. In addition, it is difficult to form the absorber member made of the foaming resin material in a specified thickness or less. Unfortunately, in a region where the gap between the bumper cover and the absorber member is small, such as in a corner section of the vehicle (outer end of the bumper cover in a vehicle width direction), there is a case that the spacer section cannot be disposed in the gap.